2006-05-16  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/22303
	* tree-ssa-ccp.c (fold_const_aggregate_ref): Handle reads
	from STRING_CSTs.
	(evaluate_stmt): Fall back to fold_const_aggregate_ref, if
	ccp_fold did not simplify the statement.

	* gcc.dg/tree-ssa/ssa-ccp-13.c: New testcase.

From-SVN: r113826